Five years ago, criminal police captain Chen Yan mistakenly signed a death warrant, and an innocent person was brought to justice. Five years later, Han Zhao, the murderer's son, recreated the method of the crime in the name of revenge, forcing him to reopen the file. Lin Qiuhe's secret report, Zhou Chongli's silent recording, and Zhao Yansheng's power cover are all entangled at every level. When Su Li's microscope revealed that his brother's blood stains matched those of the real murderer, Chen Yan finally understood that what he signed was not a death sentence, but an epitaph for the truth.
